Pipe grab



Nov. 24, 1931. w. G. wEHR l 1,833,545

PIPE GRAB Filed Nov. 22 1929 s sheets-sheet 1 lin/aufm? Nov. 24, 1931.

w. G. WEHR PIPE GRAB Filed Nov. 22.

1929 3 Sheets-Sheet 2 ,frzvez'lfoik zmmm.

Nov. 24, l931. w. G. wEHR 1,833,545

PIPE GRAB I K Filed Nov. 22. 1929 5 Sheets-Sheet 3 /2 u E 5l j l I i l l l Ll.. A l

ira-tested Nov. 24, 1931 UNITED STATES PATENT OFFICE WILLIAM G. WEHR, OF EAST CLEVELAND, OHIO, ASSIGNOR TO THE CLEVELAND CRANE & ENGINEERING COMPANY, 'OF WICKLIFFE, OHIO, A CORPORATION OF OHIO PIPE GRAB Application filed November 22, 1929. Serial N0. 409,068.

rl'his invention relates to improvements in pipe grabs, that is loading and unloading devices adapted to grasp, lift and carry a large number of pipes or the like at one time. 1i One of the objects of the invention is the provision of a hold-down which will automatically adjust itself to the top of the pile of pipe being handled.

nother object is the provision of a holddown which adjusts itself to the pile before the latter is lifted, and is maintained in operative position when a pile of pipe is deposited after the weight of the pile is taken off the grab, as distinguished from a hold-down which is drawn toward operative engagement by the weight of the pipe or other material being lifted.

Another object is the provision of a flexible hold-down which is capable of closely conforming to the contour of the pile, and of adapting itself to any changes that may occur in the arrangement of the pipes as the pile is lifted, transported and deposited.

Another object of the invention is the provision of a power operated drive mechanism for moving the feet of the grab, these feet being projectable inwardly from the legs of the grab to form the bottom support for a pileof pipes, this driving means acting positively to withdraw the feet and acting through a slip clutch to project the feet into the pile, whereby damage to the mechanism and to the pipe being handled is prevented.

Other objects and features of novelty will 3.5 appear as I proceed with the description of that embodiment of the invention which, for the purposes of the present application, I have illustrated in the accompanying drawings, in which Figure 1 is a plan view of a pipe grab embodying the invention. i

Fig. 2 is a side elevation of the same.

Fig. 3 is an end view of the structure illustrated in Figs. 1 and 2.

Fig. 4 is a view similar to Fig. 3 but showing the grab loaded with pipe.

Fig. 5 is a detail'view` partly in vertical section on the line 5-5, Fig. 3, showing the motor drive on a larger scale.

Fig. 6 is an end view, looking in the direction of the arrow 6 in Fig. 5, showing the drive gearing.

Fig. 7 is a plan view on a smaller scale illustrating the pipe grab as it is being lowered over a pile of pipe, the middle portions of the pipes being broken away for the sake of clearness, and

Fig. 8 is an end view of the same.

In Figs. 7 and 8 I have shown a pile of pipes A, retained by the standards 10 and 11, this being a common arrangement for storing pipes. The pipe grab is of a length preferably short enough to be located between the standards 10 and 11. It is adapted to be raised and lowered and moved about by means of a suitable crane, the hook of which engages beneath an arched hanger 12, comprising legs which extend through a box-like casting 13 and through parallel frame bars or tracks 14 which extend through said casting, the lower ends of the hanger legs being threaded for the reception of nuts 15, upon the upper surfaces of which the casting 13 rests. The ends of the frame consist of angle bars 16 which extend laterally in both directions beyond the parallel frame bars 14. In order to brace the frame, truss rods 17, attached to both of the angle bars 16, may connect the latter with the hanger 12 near the top thereof.

Secured to the casting 13 are two vertical plates 18, which are cut out on their lower sides to clear the pipe or other stacked material when the grab is lowered over the same and to provide depending arms spaced apart sufficiently to straddle the pile of material see Fig. 8). These depending arms may be connected at their lower extremities at each side of the device by tie-bars 19. Spaced a short distance above the tie-bars 19 shafts 2O are mounted to rotate in the plates 18. These shafts carry sprockets 21 under which pass chains 22. The two chains are connected at their respective ends by bars 23, and each of these bars at an intermediate point is connected by means of a coil spring 24 with a bracket 25 upon the hanger 12. It will be apparent that as the device is lowered over a pile of pipe, for instance, the chains 22 will engage with the uppermost pipes of the pile, and thereafter as the frame continues to de- '.59 Vtcollartogetherduring rotation ofthe gear in is entirely clear ofthe pile` the chainsass'ume the positionshownin Fig. 3 of the drzwvings.A

Extending downwardly from the ends of transverse frame members 16 are cylindrical legs 26 which are fixed rigidly in position approximately in line with the depending arms of the plates-18. .Throughthese legs extend vertical rock-shafts 27. To the lowerends of .these rock-shafts` are secured Ipipe supporting Vfeet .28 .that fare preferably tapered `toward `their free ends, and are of a length toapproX- imately meetwhen the feet areturned toward each other. 0n the upper ends of Y'the rockshafts Qtlierearefxed lever arms 29 and 30 having .hubs thickeron one `sidethanon the other, the thick side of .hubs of Y.levers 29 `beingup andthe-thick sides oflevers30 being =down -so ras to'bring .the levers :proper .to different .levels and enable .them yto clear veach ,.other.

Qn the casting13.between-thelegs ofhanger I12 I mount @an' electric motor 31 of .the ireverSibletype. Any convenientelectrical con- :snections .and switching -means for starting z-andf stopping themotorland. changing the direction -of rotation may be xemployed, such connections and Ymeansnot being illustrated 1asntheidetails of-thesame form no,par.t ofthe present invention. The motor `sh-ai't 32 eX- :ltends .into a gear casing.y 33, -where -it lis keyed to a 5pinion-34 that meshes with .a pinion,

which -in turn fmeshes with.a-gear.36. This :latter gear .is inthe form .of a counterbored ring -Which is rotatably mounted Vupon a flanged collarf37 Vthat Yis fixed-to a shaft -38 "thateeaitends :through the casting 13 and is V'mounted -for rotation therein. The .iange .oftheco'll-ar 37 iis provided wthva series of inotches39-=in which'are received balls40 that vare adapted to positivelyclutchthe gear and ronefdifrcction, and to permit vfree rotation of :the gear inthe-opposite direction. VIn other word-sthe gear36 and collar37fareconnected :by an 'overrunningclutch. 41 is a .friction clutch plate :adapted to frictiona-lly engage .aside Asurface-of ythe gear 36, .this plate being .slidably connected with the shaft 38'by-means fof .a :key 42 or the .like which prevents relao :tive'frotation :between Lthese parts. A ring 434s set-into ,a groove inethe shaft 38 Vto form fa stop against which .bears a collar 44 that constitutesIonev abutmentifor a ycoil spring 45,

fthe opposite-end-ofthe-springbearingagainst theiclutch}plate41. Hencetherotation/of the .gear Bti/ineither direction tends to actthrough the friction clutch plate 41 to rotate the shaft 38 correspondingly, but the rotation of the gear 36 in one direction causes the over-running clutch to lock the gear 36 to the collar 37 and produces positive rotation ofthe shaft 38. In the latter case, the friction clutch confnect-ion isshortl vcireuited,vso to-speak.

The ends of the shaft 38 are connected by any suitable means with oppositely threaded screwlshafts'46*and47 thatare arranged be- 7 tween and extend parallel with the frame bars 14, these screw shafts being rotatably 'mounted at their outer ends in the transverse frame bars 16. Slides 48 are threadably `mounted upon'l the vscrews 46 and 47 and have smooth bearings upon the frame bars 14.

Each of theseslidesis connected by v.a pair of links 49 with the .correspondinglever arms 29 and ,30. p

Operation.-.-Assuming that the pipe .grab

ris .connected through .the hanger .12' `vvith a craneptlie Ylattenmayfbe operated to position the apparatus above Va :pile of pipes A and loweredto cause .thelegs26 and the depending. arms..18 to .straddle the pile, as indicated in Fids. `7 .and 8. :sthe apparatus is lowered, thechains QQIengagethe-top of the-pile,

xthespringsl beinglextended to permit this action.V Thelowering Iofgthe apparatus is 1continued .until .the `feet 28, which are l.then parallel .with the ,pipes A, arerbroughtftothe desired level which, of course, may. vary .de-

.pending'uponzthe,numberofpipes which it is desiredto move. .TheimotorBl .is then caused -to vrotate 'in the :anti-clockwise direction, as

viewed fromthe right .of Fig. A.This .produces .an anti-.clockwise rotation of the'gear 36, which isthereby permitted to run on'the collar 37 without rotating .the latter. Rota- .tion .is .transmitted `to the shaft 38 however 4through .they intermediacy of 5the y slip-clutch y41. The screws 46 and 47 are therebyrotat- `edto produce outwardtravel of the slides 48,

thereby :swinging .the .Iarms "29 30 and fthe `feet .28 rfrom their .full line positions of Fig.

..1 toward .their dotted line positionsthereof.

The pointed Vends of =thefeet 28 wedge apart the pipes A inthe pile, imparting a slight llifting movement vto the. pipeslocated above the level-ofthe feet. lf one or' both pairsof Yfeet,in approachingthe-dotted line positions Iofllig. .1, should happen tofwedge themselves against the sidesof afpipe instead of working themselves between superposed pipes, as will generally occur, thel spring-s45 'will `'yield permitting the clutch plate 41 `to slip land thus preventing the feet from jamming `again-st the pipe.v Onaccount of :the inertia of the rrotating parts, such jamming might be sufiioientlytight to render it impossible for the motor, when reversed, to release the feet. Furthermore rsuch v jamming would be apt to'vbrealr some part of the mechanism or ruin the pipe Whichwasthus engaged. The pipes alcove the Yfeet28, ybeing still ref tained against outward movement by the standards 10 and 11, may now be lifted by the crane. As they clear the standards l() and ll, they necessarily move laterally to some extent, tending to fill the space between the depending arms 18. As this occurs however, 'the chains 22 automatically move to conform to the changed contour of the pile, and continue to hold the pile down securely upon the feet 28. As the crane moves, its load is apt to swing more or less, and one end may be ti ted above the other, but the chains 22 under tension engaging the uppermost pipes prevent them from sliding off the pile.

When the load is deposited, if it be between standards similar to the standards l0 and l1, the pipe grab and its load is properly positioned above the standards, the legs 26 and depending arms 18 extending laterally beyond the standards. The motor 3l is then started in a clockwise direction, causing the gear 36 to rotate clockwise, whereby it is locked to the collar 37 and the shaft 38 is turned positively to produce travel of the slides i8 inwardly from the dotted line position of F l toward the full line position thereof. As soon as the feet 28 are parted sufficiently to clear the lowermost pipe, the pipes drop down centrally between the standards of the pile on the Hoor or ground, and consequently none of the pipes in being deposited falls outside the standards of the pile. rl`he tension on chains 22 assists gravity in rolling the pipes downwardly upon the feet 28, and when the latter are finally swung outwardly to their parallel position, the lower runs o'f the chains 22 again assume a horizontal position as shown in Fig. 3 and the grab is ready to be again loaded.

lVhile in the foregoing specification and accompanying drawings I have disclosed one embodiment of the invention more or less in detail, I desire it to be understood that such detailed disclosure is primarily for the purpose of fully illustrating the invention, and is not to be construed as amounting to a limitation upon its scope.

Having thus described my invention, I claim:

l. In a pipe grab, a frame adapted to be lowered over a pile of pipe, a flexible holddown carried by said frame and extending transversely of the pile of pipe and adapted to conform to the top of the pile as the frame is lowered thereover, and means projectable across and beneath the pile to form the bottom of the grab.

2. In a pipe grab, a frame adapted to be lowered over a pile of pipe, a chain holddown carried by said frame `and extending transversely of the pile of pipe, means for taking up slack in said chain, said means being .adapted to yield as the frame descends, and means projectable across and beneath the pile to form the bottom support therefor.

8. In a pipe grab, a frame adapted to be lowered over a pile of pipe, a flexible holddown carried by said frame and extending transversely of said pile of pipe and .adapted to conform te the top of the pile as the frame is lowered thereover, said hold-down comprising a resilient element adapted to yield as the weight of the frame is applied to the hold-down, and means projectable across and beneath the pile to form the bottom support therefor.

el. In mechanism of the character described, a frame adapted to be lowered over a pile of pipe or the like, depending arms on said frame adapted to straddle said pile, rotatable elements on said arms, a flexible holddown extending' transversely of the frame and ruiming underneath said rotatable elements, the ends of said hold-down being secured to said frame, and yieldable means for takin0l up the slack in said hold-down.

5. In a Vpipe grab, a frame adapted to be lowered over a pile of pipe, a track on said frame extending lengthwise thereof, a pair of legs depending from said frame and adapted to straddle the pile of pipe, feet carried by said legs and projectable across and beneath the pile to form a bottom support therefor, a slide movable on said track and operatively connected with said feet to move the latter to and from operative position as the slide moves back and forth upon the track, and power operated means for driving said slide positively in one direction and through a slip-clutch in the opposite direction.

6. In a pipe grab, a frame adapted to be lowered over a pile of pipe, a track on said frame extending lengthwise thereof, a pair of legs depending from said frame and adapted to straddle the pile of pipe, feet carried by said legs and projectable across and beneath the pile to form al bottom support therefor, a slide movable on said track and operatively connected with said feet to move the latter to and from operative position as the slide moves back and forth upon the track, power operated means for driving said slide including a slip-clutch, and means for automatically short-circuiting said clutch during the retraction of said feet.

7. In a pipe grab, a frame adapted to be lowered over a pile of pipe, a track on said frame extending lengthwise thereof, a pair of legs depending from said frame and adapted to straddle the pile of pipe, feet carried by said legs and adapted to swing from a. position parallel with the pipe to a positiontransversethereof,a slide movable on said track, lever arms mounted for oscillatory movement upon said legs and operatively connected with said feet, links connecting the free ends of said lever arms with said slide, whereby the movement of the slide back and forth upon the track produces a swinging movement of said feet into and out of operaiso tive position, a screw operatively connected with said slide, and a motor drivlngly connected with said screw.

8. In apipe grab, a frame adapted to be lowered over a pile of pipe, a track on said `frame extending lengthwise thereof, a pair of legs dependingY from saidV frame and adapted to straddle the pile of pipe, feet carried by said legs and adapted to swing from a position parallel with the pipe 'to a position transverse thereof, a slide movable upon said track, a lever arm mounted for oscillatory movement upon each of said legs and fixed to the corresponding foot, said lever arm being arranged diagonally on one side of the transverse plane through said legs when the corresponding foot is parallel to the pipes in the pile, and being arranged. diagonally on the other side of the said plane when the corresponding oot extends inwardly in the said plane, and links connectingthe free ends of said lever arms with said slide, whereby the movement of the slide back and forth upon the track swings said feet into and out of operative position.` Y

9. In a pipe grab, a frame adapted to be lowered over a pile of pipe, a track on said frame extending lengthwise thereof, a pair of legs depending from said frame and adapted to straddle the pile of pipe, feet carried by said legs and projectable across and beneath the pile to form the bottom of the grab, a slide movable on said track and operatively connected with said feet to move the latter to and from operative position as the slide moves back and forth upon the track, a screw arranged parallel with said track and threadably connected with said slide, and a motor for rotating said screw.

In testimony whereof, I hereunto afX my signature.

WILLIAM G. 

